New High-Resolution Analysis of the nu3, nu4, and nu6 Bands of D2CO Measured by Fourier Transform Spectroscopy
A reanalysis of the nu3, nu4, and nu6 interacting bands of D2CO has been carried out in the region 850-1250 cm-1 using high-resolution Fourier transform spectra recorded at Giessen. As compared to the previous study of these bands (1987, K. Nakagawa, R. H. Schwendeman, and J. W. C. Johns, J. Mol. Spectrosc. 122, 462-476) higher J and Ka transitions were assigned for the three bands, leading to a better determination of the upper state constants. The v3 = 1, v4 = 1, and v6 = 1 experimental energy levels were introduced in a least-squares fit calculation together with the microwave measurements available in the literature in order to obtain the upper state parameters (band centers, rotational and coupling constants). In this calculation, which allowed us to reproduce both the infrared and the microwave measurements to within their experimental accuracies, the A-, B-, and C-type Coriolis interactions involving the rotational levels belonging to the v4 = 1 and v6 = 1, v3 = 1 and v4 = 1, and v3 = 1 and v6 = 1 interacting states respectively were explicitly taken into account. Finally, from the intensities, a new determination of the relative values of the q3, q4, and q6 first derivatives of the D2CO dipole moment was performed. Copyright 1998 Academic Press. Copyright 1998Academic Press
Perrin
A
CNRS, Universite Paris Sud, Bat 210, Campus d'Orsay, Orsay, Cedex, F-91405, France
Flaud
J
Predoi-Cross
A
Winnewisser
M
Winnewisser
BP
Mellau
G
Lock
M